code: def datetime_to_timestamp(dateTime):
      """Converts a datetime.datetime to a UTC timestamp."""
      diff = as_utc(dateTime) - epoch_utc
      return diff.total_seconds()
  
file_path: pyalgotrade/pyalgotrade/utils/dt.py
imports: import datetime
  import pytz
label_desc: Use image node_id 5 for calling a global function with example usage: datetime_to_timestamp(dateTime) and returns: diff